The Internet allows users to access millions of electronic documents, such as electronic mail messages, web pages, memoranda, design specifications, electronic books, and so on. Because of the large number of documents, it can be difficult for users to locate documents of interest. To locate a document, a user may submit search terms to a search engine. The search engine identifies documents that may be related to the search terms and then presents indications of those documents as the search result. When a search result is presented, the search engine may attempt to provide a summary of each document so that the user can quickly determine whether a document is really of interest. Some documents may have an abstract or summary section that can be used by the search engine. Many documents, however, do not have abstracts or summaries. The search engine may automatically generate a summary for such documents. The usefulness of the automatically generated summaries depends in large part on how effectively a summary represents the main concepts of a document.
The automatic summarization of documents could also be used to assist users in processing their electronic mail messages. Many users receive hundreds of electronic mail messages on a daily basis. It can be very time-consuming for a user to access and process each electronic mail message. Indeed, because of the large number of electronic mail messages, it may be difficult for a user to identify an important electronic mail message that may need prompt attention out of all the electronic mail messages of lesser importance. Some electronic mail systems may, when listing messages that have recently arrived, display the first line or two of the message to assist the user in identifying the topic of electronic mail messages. In addition, computing devices with small display areas, such as a cell phone, may shorten electronic mail messages to the first line or two because they cannot effectively display an entire message at one time. The first line or two of the message may, however, not be an effective summary of the message.
It would be desirable to have a technique for automatically generating effective summaries of documents. Such effective summaries would help a user identify documents of interest, organize electronic mail message, view documents on devices with limited display space, and so on.